Theo Sandfort, PhD, is Professor of Clinical Sociomedical Sciences (in Psychiatry) at Columbia University and Research Scientist at the New York State Psychiatric Institute. He is Director of the Development Core at the HIV Center for Clinical and Behavioral Studies and Director of the postdoctoral research training program “Behavioral Sciences in HIV Research.” Dr. Sandfort is trained as a social psychologist. Until 2001, he worked in the Netherlands, amongst others as Chair of the Gay and Lesbian Studies Department at Utrecht University.

He has over 35 years of experience in quantitative and qualitative social science research in sexuality, including on sexual development, determinants of HIV risk in gay and bisexual men, HIV prevention in the general population, sexual orientation and mental health, sexual orientation and gender-role identity, gay and lesbian stigma and discrimination, and the role of healthcare providers in STI prevention and sexual counseling. In the past 15 years, he conducted research in Southern and Eastern Africa focused on HIV risk in sexual and gender minority populations. He is on the editorial board of several major academic journals, including AIDS Care, Culture, Health and Sexuality, Archives of Sexual Behavior, LGBT Health, and Journal of Sex Research.